Did you sign a settlement agreement before you resigned?  If so, did it contain a confidentiality agreement?

I left the government four years ago under some unusual circumstances.  This is what happened.  I was in Federal Law Enforcement for 13 years and at no time had I ever received any type of discipline.  I worked as Internal Affairs and needless to say I was not the most liked person.  I was investigated for inapropriate conduct 2 times.  One investigation was cleared.  One investigation was not.  After reporting my supervisor for wrong doing....he was investigated and cleared.  Not long after that I was being investigated.  The charges were misconduct.  Some people that my supervisor and I were close to turned on me.  We had conversations like locker room talk for approximately two years and they reported this.  Not timely I may add.  Yes I was wrong for engaging in this type of conversation and I acknowledged this.  At the completion of the investigation and before any determination was made, I resigned.  I was just tired of this environment so i resigned.  Now four years later, I am applying for a contract job that requires me to complete the SF 86.  Now.....my question is how do i answer how I left this job.  It was unfavorable conditions but I did not stick around to see the outcome.  I know they sustained the investigation because I admitted what I said.  But I dont know exactly what the employing agency intended to do.  Can this eliminate me?